Sound-reproducer.



PATENTED DEC. 29, 1903.

T. H. MACDONALD. SOUND REPRGDUGER.

' APPLIOATION FILED APR. 17, 903.

N0 MODEL.

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awumfoz a/vi bwmm UNITED STATES i atented December 29,1903.

PATENT OFFICE.

THOMAS H. MACDONALD, OF BRIDGEPORT OONNECTICUT, ASSIGNOR TO AMERICAN GRAPHOPHONE COMPANY, OF WASHINGTON, DISTRICT OF COLUMBIA, A CORPORATION OF WEST VIRGINIA.

SOUN-D-REPRODUCER.

SPECIFICATION forming part of Letters Patent No. 747,991, dated December 29, 1903.

Application filed April 17, 1903. Serial No. 153,144. (No model.)

To all whom it may concern:

Be it known that I, THOMAS H. MACDON- ALD, a resident of Bridgeport, Connecticut,

have invented new and useful Improvements.

which is usually attached by means of a spring I to the diaphragm-box, the resiliency of the spring permitting limited vibration of the bar. According to this invention the bar is loosely mounted, preferably passing through a hole in the casing of such size that it does not touch the same in operation. To the stylus-bar is rigidly fastened a guide rod or wire, preferably in the form of a staple,whose ends are fitted and play with slight friction in holes drilled therefor in the casing. This construction avoids the use of springs, and

the parts can be very cheaply and quickly made and assembled.

In the accompanying drawings, Figure 1 is a front elevation; Fig. 2, a section lengthwise c of the stylus-bar, and Fig.3 a. part section transverse to the latter.

The stylus-bar A is attached at one end to the diaphragm B in any suitable way and at the other has a socket for reception of the stylus or needle a, which is held in place by set-screw 17. Bar A passes through a hole 0 in diaphragm box or casing C, the hole being of such size that the bar A does not touch the casing. To the bar A is attached a guide (1, consisting, as shown, of a piece of wire bent to U shape, the ends of the guide being inserted in holes drilled in flange c of the casing C, in which they fit snugly so as to play with slight friction. Obviously the guide-wire could be fastened to the casing and fit loosely in the bar, this being simply a reversal of the construction.

I claim- 1. In a sound-reproducer, a stylus-bar passing freely without contact through an aperture in the casing, and having a guide rod or wire attached to said bar and playing freely with slight friction in a hole in said casing. 2. In combinationwith the diaphragm and its casing, a stylus-bar attached at one end to said diaphragm, and a U-shaped guide secured to said bar, its ends playing loosely in holes in said casing.

In testimony whereof I have signed this specification in the presence of two subscribing witnesses. 1

THOMAS H. MACDONALD.

Witnesses:

A. B. KEOUGH, M. A. Foeo. 

